NASA Mars Opportunity discovers clays favourable to Martian biology

The pale rock in the upper center of this image, about the size of a human forearm, includes a target called “Esperance,” which was inspected by NASA’s Mars Exploration Rover Opportunity.

Data from the rover’s alpha particle X-ray spectrometer (APXS) indicate that Esperance’s composition is higher in aluminum and silica, and lower in calcium and iron, than other rocks Opportunity has examined in more than nine years on Mars. 

Preliminary interpretation points to clay mineral content due to intensive alteration by water. 

Credit: NASA/JPL-Caltech/Cornell/Arizona 

Now nearly a decade into her planned 3 month only expedition to Mars, NASA's longest living rover Opportunity, struck gold and has just discovered the strongest evidence to date for an environment favourable to ancient Martian (organic) biology – and she has set sail hunting for a motherlode of new clues amongst fabulous looking terrain.

Barely two weeks ago in mid-May 2013, Opportunity's analysis of a new rock target named "Esperance" confirmed that it is composed of a "clay that had been intensely altered by relatively neutral pH water – representing the most favorable conditions for biology that Opportunity has yet seen in the rock histories it has encountered," NASA said in a statement.

The finding of a fractured rock loaded with clay minerals and ravaged by flowing liquid water in which life could have thrived amounts to a scientific home run for the golf cart sized rover!

"Water that moved through fractures during this rock's history would have provided more favorable conditions for biology than any other wet environment recorded in rocks Opportunity has seen," said the mission's principal investigator Prof. Steve Squyres of Cornell University, Ithaca, N.Y.

Opportunity accomplished the ground breaking new discovery by exposing the interior of Esperance with her still functioning Rock Abrasion Tool (RAT) and examining a pristine patch using the microscopic camera and X-Ray spectrometer on the end of her 3 foot long robotic arm.

The robot made the discovery at the conclusion of a 20 month long science expedition circling around a low ridge called "Cape York" – which she has just departed on a southerly heading trekking around the eroded rim of the huge crater named "Endeavour."

"Esperance was so important, we committed several weeks to getting this one measurement of it, even though we knew the clock was ticking."

Esperance stems from a time when the Red Planet was far warmer and wetter billions of years ago.

Close-Up of ‘Esperance’ After Abrasion by Opportunity 

This mosaic of four frames shot by the microscopic imager on the robotic arm of NASA’s Mars Exploration Rover Opportunity shows a rock target called “Esperance” after some of the rock’s surface had been removed by Opportunity’s rock abrasion tool, or RAT. 

The component images were taken on Sol 3305 on Mars (May 11, 2013). 

The area shown is about 2.4 inches (6 centimeters) across. 

Credit: NASA/JPL-Caltech/Cornell/USGS

MARS Simulation on Tenerife mountain top

One of the most exciting parts of my astrobiology research is working out how to search for evidence of past Martian life - signs of ancient biology that may have fallen extinct hundreds of millions of years ago.

One promising technique for finding these "biosignatures" - which could be pockets of organic molecules or even microbial life - is to entice them to glow in the dark using an ultraviolet laser mounted on a robotic probe. A camera on the probe would then detect the glow.

If you've ever had a gin and tonic in a nightclub you are probably already familiar with this effect. You'll have noticed how the ultraviolet lights in the club (we see them as black) cause the G&T to emit an eerie blue glow. This is caused by quinine, an organic molecule in the tonic water, fluorescing. It is this bitter-tasting compound that gives tonic water its anti-malarial properties so it's funny to think how far we've come since Victorian colonists in East Africa supped medicinal G&T sun-downers!

I have been testing this technique in the lab but it is now time to try the equipment in a more realistic scenario. So next week I'm flying out to Tenerife in the Canary Islands to carry out fieldwork in the volcanic caldera that sits like a giant pimple on the face of this tiny island. The barren rocky terrain and volcanic geology around Tenerife are a good approximation to the Martian landscape, and, in fact, prototypes for Mars rovers are put through their paces here.

I am part of a team of scientists, lead by Derek Pullan at Leicester University, who will be field-testing different instruments and camera systems. The system I'll be testing involves a sensitive digital camera and an ultraviolet light source. Because we'll be operating by day I'll have to shield everything from the bright sunlight beneath a thick photographic blanket. My rucksack will also be laden with other snazzy kit like a laser range-finder and GPS-equipped camera to record the environment around my test sites.

There are still a few things to sort out, but I'm pretty much good to go now. Holiday snaps to follow!

The Thylacine enigma: A Marsupial Wolf or a Tasmanian Tiger?

A study of the bones of the now extinct thylacine, called both a marsupial wolf and a Tasmanian tiger, has determined that the solitary, ambush-style predator was more cat than dog but also clearly a marsupial.

“We provide quantitative support to the suspicions of earlier researchers that the thylacine was not a pursuit predator,” says Borja Figueirido, a postdoctoral researcher at Brown University and the paper’s lead author.

The research is reported in the journal Biology Letters.

“Although there is no doubt that the thylacine diet was similar to that of living wolves, we find no compelling evidence that they hunted similarly.”

For millions of years, Thylacinus cynocephalus roamed mainland Australia. Its numbers declined as humans settled throughout the continent, beginning some 40,000 years ago and as the dingo, a small, dog-like animal, was introduced, about 4,000 years ago.

Thylacines’ last remaining outpost was in dingo-free Tasmania, but a concerted eradication effort wiped out the species. The last known thylacine died at a zoo in 1936.

It’s unclear why the animal fared so poorly with the arrival of humans and dingoes, but speculation is that human activity disrupted the thylacine habitat and perhaps its food sources.

The role dingoes had on the thylacine demise is less clear. Speculationis that because dingoes were the placental spitting image of the marsupial thylacines, evolved in isolated settings, called evolutionary convergence. When dingoes arrived in Australia, they helped push the thylacines out.

But Figueirido and Christine Janis, professor of biology and a co-author on the paper, say there’s more to the story.

The researchers compared the thylacine’s skeleton with pumas, panthers, jackals, wolves, hyenas, and Tasmanian devils, that are the largest living carnivorous marsupials.

Previous research had discovered the elbow joint is a clue to predator habits, because it shows whether the animal is built for flexibility and dexterity in handling prey or for chase and speed in tracking down the next meal.

Figueirido and Janis found that the thylacine’s humerus, or upper arm bone, was oval and elongated at the end closest to the elbow, implying that the animal’s forearm bones, the radius and ulna, were separate.

That means the Tasmanian tiger would have been able to rotate its arm so that the palm faced upwards, like a cat. The distal humerus on dog-like animals, such as dingoes and wolves, is more squared-up and shorter.

This indicates the radius and ulna were closer together in these species, reflecting that these animals’ hands are more fixed in the palm-down position.

In terms of hunting, the increased arm and hand movement would have given the thylacine a greater capability of subduing its quarry after a surprise attack. Since dingoes and other dog-like creatures have less latitude in arm-hand movement, that helps explain why these animals hunt by pursuit and in packs, rather than in an ambush setting.

“It’s a very subtle thing,” says Janis. “You never would think that the shape of just one bone would mean so much.”

Some cats, like cheetahs, use speed to catch their quarry, while some canid species, like foxes, rely more on the guile of the ambush. Janis says the thylacine’s hunting tactics appear to be a unique mix. “I don’t think there’s anything like it around today. It’s sort of like a cat-like fox.”

What that means for the dingo’s role in the thylacine’s disappearance from continental Australia is not clear, but it does show the animals, while similar in many respects, likely hunted differently, Janis says.

“Dingoes were more like the final straw (to the Tasmanian tigers’ demise in continental Australia), because they weren’t in the same niche. It’s not just that a dingo was a placental version of a thylacine.”

The research was funded in part by the Bushnell Foundation.

More news from Brown University: http://news.brown.edu

First All-Digital Science Textbook Will Be Free

Science textbooks are born as clunky, out-of-date tomes the moment they roll off the printing press. Research simply moves too fast for the publishing industry to keep up. Digital texts could end this cycle.

Textbooks designed to be all-digital and interactive from the start (as opposed to simply converting print books) could bring not only salvation to schools because they’re easily updated, but also a revolution in how students learn science. Yet publishers are comfortable with a $5 billion-per-year college textbook industry that has recently seen price increases outpace inflation by more than 250 percent, and 99 percent of the market is tied to paper.

One not-for-profit organization is done waiting for the digital textbook revolution.


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Synthetics and Biology: Is it a working Partnership?

"Plastics" may have been the Baby Boomer watchword, but "synthetic" rules today.

That's "synthetic" as in synthetic biology, the hottest biomedical buzzword, promising new drugs, new fuel and someday, new life.

"If we can make life, then we understand it," says molecular biologist Steven Benner of the Foundation for Applied Molecular Evolution in Gainesville, Fla.

Starting with the building blocks of animal and plant cells, synthetic biologists are reengineering living things today and hope to create synthetic life tomorrow. The ultimate goal, Benner says, is "synthesizing life from scratch."

That makes experts, including human genome pioneers Craig Venter of Rockville, Md., and Jay Keasling of the University of California-Berkeley, hopeful and cautious at the same time about the promise and peril of the field.

In July, a team led by Carole Lartigue of the J. Craig Venter Institute in Rockville, Md., reported the field's latest advance in the journal Science: a way to genetically engineer bacteria, previously considered impossible. "Nobody else has done anything remotely like this before," Venter says.

The immediate application is engineering defanged vaccine strains for use against the bacteria family chosen for the study. But a lot of other ideas are cooking, from saving the planet from global warming to figuring out just how life started in the first place.

The promise

In 1974, oncologist Wac{lstrok}aw Szybalski of the University of Wisconsin Medical School in Madison coined the term "synthetic biology" as a way to describe biologists shuffling genes among organisms. The term has taken on multiple meanings since then in science, says David Rejeski of the Synthetic Biology Project at the Woodrow Wilson International Center for Scholars in Washington, D.C. The public largely has no clue, he says: "Nobody really knows what it is."

One popular definition championed by MIT's Drew Endy, who founded the non-profit Biobrick Foundation, is an engineering one, in which the parts of cells act as the screws, bolts, bricks and mortar of future biology. Others, such as Venter and Harvard's George Church, talk of building completely man-made cells, with parts all made from scratch.

Some recent innovations:

• Last year, Keasling's lab unveiled bacteria that make the anti-malaria drug artemisinin by transferring 14 genes into a microbe.

• Benner's lab has created an artificial form of DNA that uses six chemicals for the "bases" of a genetic code, unlike the four found in human DNA.

• In March, Church announced the creation of artificial "ribosomes," cellular factories that take messenger genes and make proteins that keep cells alive.

"Over the next 25 years, synthetic biologically engineered antibiotics could be developed which monitor the adaptation of the bacteria they are designed to kill, and modify their response accordingly," says Richard Kitney of the United Kingdom's Imperial College. "Similarly, synthetically engineered T-cell (immune cell) components could be used to develop a device which is capable of finding and killing cancerous cells."